Power flaring tool



y 1965 R. G. RASMUSSEN 3,

POWER FLARING TOOL Original Filed Sept. 22, 1958 INVENTOR. ROBERT G. RASMUSSEN BY 0%, 2 fpowrui? AT TQRNEYS 1958. This application Nov. 19, I962, Ser. No. 239,37 13 (Ilairns. (Cl. 72-56) The present invention relates generally as indicated to a power flaring tool and more particularly to a self-contained, portable power flaring tooladapted to be used as in connection with the flaring or flanging the ends of tubes and the like. This is a continuation of my copending application, Serial No. 762,579, filed September 22, 1958, entitled Power Flaring Tool and now aban- .doned.

Hitherto, tube flaring tools have, for the most part, been of the impact type wherein a conical flaring head is forced against the end of a tube as by a succession of hammer blows, the tube being held between separable clamping jaws that define a countersink or female die against which the end portion of the tube is flared by the succession of blows of the flaring head. In the flaring of hard alloy tubes, heavy wall tubes, etc. it is necessary to strike the flaring head a number of blows and obviously, with certain tube metals such as those that work-harden, the flaring operation becomes increasingly diflicult with each successive blow. Moreover, the work-hardened end portion of such tube is apt to split before the flare has been completed. On the other hand, in the flaring of very soft tubes as of aluminum, lead, or the like the flaring headmay be struck too-heavy blows resulting in excessive thinning of the flare.

It also has been proposed heretofore to employ flaring tOOls'in which the flaring head is screw-actuated to engage and flare the clamped tube. With this type of flaring tool the tube must be especially firmly gripped and, in the case of high strength alloys, it is practically impossible to flare the tube end by such slow application of flaring force; and besides, tubes that work-harden are apt to split before the Hare is completed.

Electric motor operated flaring tools have also been designed, these usually being provided with eccentric rotary flaring heads which flare the tubes when advanced to ward the clamped ends thereof. Such tool, not only requires connection with an electric power source, but also,

effects work-hardening of the tube metal thereby requiring application of large forces. Of course, as previously mentioned, there is the danger of splitting of the work hardened end portion of the tube;

With the foregoing in mind, it is a principal object of this invention to provide a power flaring tool which is of the percussion or impact type and requires but a single blow from the flaring head to complete the flaring opera. tion on the tube. W

It is another object of this invention to'provide a power flaring tool in which the flaring head is in the nature of a projectile shot out of a' gun with predetermined momentum to strike the tube end and to flare it with a single blow without opportunity for work-hardening and splitting of the tube. a

It is another object of this invention to provide a cornbination gun and flaring tool in which the actuation of the gun to release the trigger lock thereof automatically actuates the tube clamp to securely grip clamping dies of the flaring tool.

the tube in the United States Patent dies on the tube; and

g, ammo Patented July 13, 1965 It is another object of this invention to provide a gun and flaring tool combination in which the flaring head is actuated by a slug in the barrel of the gun, the slug engaging the flaring head to shoot it toward the end of the tube under the influence of an exploding charge in the gun chamber.

It is another object of this invention to provide a gun and flaring tool combination as aforesaid in which dashpot means are provided for decelerating the slug when the flaring head strikes the end of the tube.

It is another object of this invention to provide a power flaring tool that is equipped with anautomatic tube 10- cating stop. I 7

It is another object of this invention to provide a power flaring tool in which the force of the flaring blow may be varied over a wide range to properly flare tubes of different diameters and metals.

It is another object of this invention to provide a power flaring tool whichis self-contained and portable without requiring any connection to electric power lines, air pressure lines,or the like.

Other objects and advantages of the present invention will become apparent as the following description 'proceeds.

To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed draw ings setting forth in detail a certain illustrative embodiment of the invention, this being indicative, however, of but one of the various ways in which theprinciple of the invention may be employed.

In said annexed drawings:

FIG. 1 is a side elevation view, partly in cross-section, of the present power flaring tool;

, FIG. 2 is a fragmentary cross-section view showing the tube as flared by the flaring head;

FIG. 3 is a transverse cross-section view taken substantially along the line 33, FIG.- 1, showing the actuator for the tube clamping jaws and further showing the automatic locating stopfor the tube end which is moved out of the way responsive to closing of the clamping jaws or FIG. 4 is an end elevation view showing the jaws in open position and showing the tube locating stop in position to constitute a stop for the end of the tube which is to be flared. V 7

Referring now more particularly to the drawings, the reference numeral 1 denotes a conventional gun or fastener driving tool such as is in prevalent use. in the building trades in the shooting of fasteners such .as screws,

( anchor bolts, etc. into masonry walls, and into concrete. ceilings, walls, and floors.

In the example shown, the gun I is provided with a handie 2, a trigger 3 and trigger guard 4, the trigger 3 when drawn toward the left as viewed in FIG. 1 being operative to trip a hammer which, in turn, causes a firing pin to engage the cap of a blank cartridge loaded in the chamfirearm art and may essentially be of the types employed" her 5 of a barrel. The details of construction of the been shown herein since these are well-known in the in pistols and other guns.

In any case, it is preferred to pivotally mount the barfacilitate reloading with blank cartridges.

flaring tool.

onto the front endof the ,inner trigger release barrel assembly 8'which"operates the;trigger release mechanism (not shown), a guard plate :whichservesto protect the operator from flying pieces of brick, concrete, and the like and which also positionsthe axis of the barrel assembly 6 perpendicular to the ceiling, wall, or floor into which the projectile is to be shot. V 9 In"the present case, instead ofproviding such guard plate, there is screwed on the front end of the inner trigger release barrel 8 the flaring tool 10 which, in combination with the gun I, constitutes the present power The portion of the flaring tool 10 that'is screwed onto the end of the inner triggerrelease barrel 8 is in the form of a heavy tubular block 11 mounting a tubular flaring head guide 12thereon. [The flaring head guide 12 fixedly mounts a die-receiving shell 14 in which a tube clamping die member or jaw -15 is adapted to be assembled'as bymeans of the screw 16. a v a Pivotally mounted on the 'pin '17 is a complemental halfshell 18 in which is replaceably mounted by screw 19 the movable tube clamping jaw 20. Saidjaws 15 and 20 are formed with complemental semi-circular bores which, when in mating engagement form a circular bore 21 of slightly smaller diameter than the tube T which is to be flared, said bore 21 terminating in a countersink 23 that constitutes a'female die seat against which the tube T is adaptedto be flared. 7

The fixed shell 14 is provided with a radially extending lug 24 to which the lever 25 is pivotally mounted on the 'pin 26 and the movable shell 18 is provided with a similar lug27 having a beveled outer face 28"that cooperates with the beveled inner face 29 of the lever 25 so that when saidlever is swung in a clockwise direction to the position shown in FIG. 1, the tube clamping jaws 15 and 20 are drawn tightly together to clamp the tube T which is to be flared. As evident, when the gun "1 is to be fired to perform-the flaring operation which will be presently described, the drawing of the lever 25 toward stop 40. Now, when the movable jaw 20 is swung toward closed position and when the lever 25 is swung to lock the jaws, a cam 42 on the movable jaw 20 automatically pushes the stop 40 out of the'way to a position radially outside the tube T.

When the tube T is in place and when the clamping lever 25 and the handle 2 of the gun 1 are relatively moved toward each other, the inner trigger release barrel 8 is moved to release the trigger lock, whereupon, when the operator squeezes the trigger 3 a blank cartridge in the firing chamber 5 is fired and the gas under presg of charges and sizesof cartrid-ges, the flaring head 31 may be shot against the tube end with any desired force so as to completely flarethe tube T without thinning excessively with a single blow of th'e'flaring head 31 against the end of the tube T.' r p The intermediate tubular block 11 which is screwed onto the inner trigger release barrel 8 and onto which the flaring head guide 12 is screwed, has a dashpot associated therewith which includes a thimble 45 screwed into said block 11 and forming a closed chamber with the collar l of the slidable dashpot member 46. Orifices 47in dashpot member control the rate of movement of said memher 46. Thedashpot member 46is normally held in the position shown in FIG. '1 by means of the compression spring 48 and'is arranged to be engaged by the slug 36..at the time that the flaring head 31 strikes the end of the left will force the, trigger release barrel 8 to the left to release the trigger 3 thereby assuring that-thetube T will be clamped firmly between the jaws 15 and 20 before the trigger 3 is unlocked for firing of the gun 1. w

.The flaring head guide 12 slidably mounts the conical flaring head 31 for movement of its conical end surface toward and into engagement with the end, of the tube T that is clamped between the jaws 15 and 20. The flar-. ing head 31 is retained at its retracted position by one or more spring detents 32 which engage in a peripheral groove 34 formed around the flange or collar of said flaring head 31. Extending rearwardly from the flaring head 31 is the rod 35 which extends, with clearance, into the bore 9 of the inner triggerrelease barrel 8, such rod 35 terminating short of the cartridge chamber 5 to the tube T," whereby there will be no tendency of the slug 36bouncing back into the chamber 5 of the gun I. When .the energy'of the slug 36 has been dissipated, the spring 48 will return the dashpot member46 to the FIG. 1 position. V

After the flaring operation has been completed the flaring head 31 is returned back to its starting position as, by means of the 'retractible sleeve 50 which-is disposed about the flaring head guide 12 and which is normally held'in the FIG. l-position by spring 51. The sleeve 50 has a, finger 52 extending inwardly through slot 53 of guide 12 toengage the collar of the flaring head-31 to pull'the latter back to itsinitial position whereat it is releasably held by the spring detents 32. The slot 53 also wise direction whereupon the-movable jaw 20 and shell 18- allow room for a slug 36 that is slidablein the bore of the therewith an automatic tube stop 40 which, when the clampingjaws are'separated, is urged by spring 41 :toa.

position radially inward of the semi-circular opening in the fixed jaw 15. Accordingly, when itis desired to flare the end of a tube T and with the clamping jawsin open position, the tube T is slipped into the openingin' the,

fixed clamping jaw 15 with the end engaged against the may be swung to open, position and the, flared tube T laterally and axially --withdr,awn. The next tube T is then slipped into placein the fixed jaw 15 with its end in engagement wth the automatic stopmeniber 40'.

The handle 2 of the gun is then swlung about the pin 7 for reloading with the next blank cartridge. A characterizing feature of this invention is that the'flaring head has a substantial mass and has astroke. several times the diameter of the tubQTwhereby'it acquires substantial'energy to, sharply rap the-tube T so as toquickly and accurately form the'flareat'hereon in: just a single blow.

Other modes of applying the pnincipleof the invention may be employed,- change being made as regards the details described, provided the features st-atedin any of the following claims or the equiv al'ent ofsuch be employed.

, I, therefore,v particularly point out "and distinctly claim as my invention: s r a 1. A power tube flaring device comprising a gun of the type having a firing chamber, and a retractible trigger lock barrel assembly; a flaring mechanism mounted on said barrel assembly and provided with a movable flaring head adapted to be propelled in response to the firing of an explosive charge in said chamber, with tube holding means arranged to hold a tube so that its end is struck and flared by said head, an actuator for closing said tube holding means upon a tube and for retracting said trigger lock barrel assembly by moving said flaring mechanism relative to said gun for firing of said gun, and a tubular body constituting guide means for movement of said flaring head toward a tube held by said tube holding means.

.2. The power tube flaring device of claim 1 wherein said tube holding means comprises separable tube clamp ing jaws, and wherein said actuator comprises a movable lever that has wedged engagement with said jaws to close said jaws upon a tube when force is applied on said lever in a direction to retract said barrel assembly.

3. The power tube flaring device of claim 1 wherein said mechanism has a movable stop member which is disposed to be engaged by the end of a tube inserted in said tube holding means, and wherein a stop actuator is provided on said tube holding means to move said stop member clear of the end of the tube in response to actuation of said tube holding means to a position holding the inserted tube.

4. The power tube flaring device of claim 3 wherein said tube holding means comprises a pair of separable clamping jaws, one of which is fixedly mounted on said mechanism and with respect to which said stop member is movable, and the other of which is movable to grip a tube against said one jaw and includes an abutment to engage and move said stop member, as aforesaid.

-5. The power tube flaring device of claim 1 wherein a slug tslidably sealed in said barrel is propelled under the influence of an explosive charge fired in said chamher and is effective to engage and move said flaring head to strike the tube held by said tube holding means.

6. The power tube flaring device of claim 5 wherein said tool has dashpot means operative to decelerate said slug while said flaring head continues freely to move into engagement with the end of the tube.

7. A power tube flaring device comprising a gun of the type having a firing chamber, and a retractible trigger lock barrel assembly; and a flaring mechanism mounted on said barrel assembly and comprising a flaring head guide, a flaring head movable in said guide and having a portion thereof extending into said barrel assembly for propulsion responsive to firing of an explosive charge in said chamber, a pair of separable clamping jaws including a fixed jaw on said guide and a movable jaw arranged to grip a tube in position for striking and flaring of the end thereof by said flaring head, and a jaw actuator movably mounted on said fixed jaw and operative to close said jaws to grip a tube therebet-ween and to move said flaring mechanism relative to said gun to retract the trigger lock barrel assembly for firing of said gun.

8. The power tube flaring device of claim 7 wherein said guide has a retractible member thereon through which said flaring head is retracted for propulsion toward the end of a tube gripped between said jaws.

9. The power tube flaring device of claim 8 wherein said guide has a spring detent yieldably engaging said flaring head when retracted as aforesaid.

10. In a power flaring device capable of flaring a tube with but a single blow, comprising a hollow elongated tubular body, a firing chamber in one end thereof, a flaring tool at the other end thereof, said flaring tool including a flaring head and a reduced diameter shank portion exposed to such firing chamber, said shank portion and thus said flaring head being adapted to be propelled in response to the firing of an explosive charge in such chamber, die clamp means secured to said tubular body adapted to hold a tube so that its end is struck and flared by said head; means yieldably to hold said flaring head and shank portion in retracted position prior to such firing of an explosive charge in such chamber, stop means mounted for movement into the path of the end of the tube properly to position such tube with respect to said die clamp means, and stop actuator means effective to move said stop member clear of the end of the tube responsive to closing of said die clamp means upon such tube.

11. In a power tube flaring device capable of flaring a tube with but a single blow, comprising a hollow elongated tubular body, a firing chamber in one end thereof, a flaring tool at the other end thereof, said flaring tool including a flaring head and a reduced diameter shank portion exposed to such firing chamber, said shank portion and thus said flaring head being adapted to be propelled in response to the firing of an explosive charge in such chamber, die clamp means secured to said tubular body adapted to hold a tube so that its end is struck and flared by said head, means frict ionally yieldably to hold said flaring head and shank portion in retracted position prior to such firing of an explosive charge in said chamber, tubular flaring head guide means properly to guide said flaring head to strike such tube end, said reduced diameter shank portion being guided in said hollow tubular body thus to provide a double guide for such flaring head and shank portion, said die clamp means comprising relatively movable tube engaging jaws, wedge means acting on said jaws operative to close said jaws upon such tube, movably mounted stop means properly to position such tube with respect to such die clamp means, and means to facilitate the movement of said stop member clear of the end of the tube prior to the firing of such explosive charge.

12. 'In a power flaring device capable of flaring a tube with but a single blow, comprising a hollow elongated tubular body, a firing chamber in one end thereof, a flaring tool at the other end thereof, said flaring tool including a flaring head and a shank portion exposed to such firing chamber, said shank portion and thus said flaring head being adapted to be propelled in response to the firing of an explosive charge in such chamber, die clamp means secured to said tubular body adapted to hold a tube so that its end is struck and flared by said head; means yieldably to hold said flaring head and shank portion in retracted position prior to such firing of an explosive charge in such chamber, stop means properly to posltion such tube with respect to said die clamp means, stop actuator means effective to move said stop member clear of the end of the tube, and safety interlock means operative to preclude firing of such explosive charge prior to the movement of said stop member clear of the end of the tube.

13. In a power tube flaring device capable of flaring a tube with but a single blow, comprising a hollow elongated tubular body, a firing chamber in one end thereof, a flaring tool at the other end thereof, said flaring tool including a flaring head and a shank portion exposed to such firing chamber, said shank portion and thus said flaring head being adapted to be propelled in response to the firing of an explosive charge in such chamber, die clamp means secured to said tubular body adapted to hold a tube so that its end is struck and flared by said head, means frictionally yieldably to hold said flaring head and shank portion in retracted position prior to such firing of an explosive charge in said chamber, tubular flaring head enclosure means enclosing said flaring head as it moves to strike such tube end, said shank portion being guided in said hollow tubular body thus to provide a guide for such flaring head and shank portion, said die clamp means comprising relatively movable tube engaging jaws, wedge means acting on said jaws operative to close said j-aws upon such tube, and stop means movable to a position for locating the tube with respect to such die clamp means 

1. A POWER TUBE FLARING DEVICE COMPRISING A GUN OF THE TYPE HAVING A FIRING CHAMBER, AND A RETRACTIBLE TRIGGER LOCK BARREL ASSEMBLY; A FLARING MECHANISM MOUNTED ON SAID BARREL ASSEMBLY AND PROVIDED WITH A MOVABLE FLARING HEAD ADAPTED TO BE PROPELLED IN RESPONSE TO THE FIRING OF AN EXPLOSIVE CHARGE IN SAID CHAMBER, WITH TUBE HOLDING MEANS ARRANGED TO HOLD A TUBE SO THAT ITS END IS STRUCK AND FLARED BY SAID HEAD, AN ACTUATOR FOR CLOSING 